Pediatric and Adult Defibrillator

ABSTRACT

This document describes an automated external defibrillator comprising a control configured to switch between a pediatric operating mode and an adult operating mode, wherein each operating mode comprises a mode-specific energy configuration and a mode-specific user configuration; an indicator configured to provide an indication of the operating mode in use during a resuscitation process; one or more processors configured to switch to the mode-specific energy configuration and the mode-specific user configuration upon a change of operating mode between the pediatric operating mode and the adult operating mode such that the automated external defibrillator delivers a defibrillating shock to a patient based on the mode-specific energy configuration; and an interface of the automated external defibrillator provides resuscitation instructions to a user based on the mode-specific user configuration.

CLAIM OF PRIORITY

This application claims priority under 35 USC §119(e) to U.S. PatentApplication Ser. No. 62/300,535, filed on Feb. 26, 2016, the entirecontents of which are hereby incorporated by reference.

TECHNICAL FIELD

This application relates to the field of adult and pediatricdefibrillation and defibrillation equipment.

BACKGROUND

Sudden health problems such as sudden cardiac arrest and injuries causedby accidents result in death and/or permanent injury of thousands ofpeople every year. Fast and competent care to resuscitate such victimsof these problems can be essential to positive outcomes in suchsituations. For example, it is said that the chance of surviving asudden cardiac arrest falls by ten percent for every minute of delay inproviding effective treatment.

Resuscitation treatments for patients suffering from cardiac arrestgenerally include clearing and opening the patient's airway, providingrescue breathing for the patient, and applying chest compressions toprovide blood flow to the victim's heart, brain, and other vital organs.If the patient has a shockable heart rhythm (ventricular fibrillation orpulseless ventricular tachycardia), resuscitation also may includedefibrillation therapy.

SUMMARY

This document describes an automated external defibrillator having acontrol configured to switch between a pediatric operating mode and anadult operating mode, wherein each operating mode comprises amode-specific energy configuration and a mode-specific userconfiguration; an indicator configured to provide an indication of theoperating mode in use during a resuscitation process; one or moreprocessors configured to switch to the mode-specific energyconfiguration and the mode-specific user configuration upon a change ofoperating mode between the pediatric operating mode and the adultoperating mode such that the automated external defibrillator delivers adefibrillating shock to a patient based on the mode-specific energyconfiguration; and an interface of the automated external defibrillatorprovides resuscitation instructions to a user based on the mode-specificuser configuration.

In some implementations, the control of the automated externaldefibrillator is further configured to switch by toggling the operatingmode of the automated external defibrillator back and forth between thepediatric operating mode and the adult operating mode. In someimplementations, the control is further configured to switch theoperating mode when the one or more computer processors determine thatthe electrode assembly in communication with at least one of theelectronic ports is usable in both the pediatric operating mode and theadult operating mode.

In some implementations, the one or more computer processors areconfigured to determine when the electrode assembly is configured onlyfor the pediatric operating mode, and, in response, the indicatorautomatically indicates the pediatric operating mode, and the control isdisabled. In some implementations, the one or more computer processorsare configured to determine when the electrode assembly is configuredonly for the adult operating mode, and, in response, the indicatorautomatically indicates the adult operating mode, and the control isdisabled. In some implementations, the automated external defibrillatorcan have a user interface configured to provide at least one ofinstructions specific to the pediatric operating mode and instructionsspecific to the adult operating mode. In some implementations, the userinterface includes a visual display configured to provide the at leastone of instructions specific to the pediatric operating mode andinstructions specific to the adult operating mode.

In some implementations, the one or more computer processors areconfigured to enter the pediatric operating mode and, in response, causethe user interface to provide the instructions specific to the pediatricoperating mode. In some implementations, when the automated externaldefibrillator is in the pediatric operating mode, the user interface isconfigured to omit chest compression feedback provided to a user. Insome implementations, the one or more computer processors are configuredto enter the adult operating mode and, in response, cause the userinterface to provide the instructions specific to the adult operatingmode. In some implementations, the user interface is configured totoggle between the instructions specific to the pediatric operating modeand the instructions specific to the adult operating mode when thecontrol is used to toggle between the modes.

In some implementations, the user interface is configured to togglebetween the instructions specific to the pediatric and adult operatingmodes during administration of one or more steps of resuscitation. Insome implementations, the user interface is configured to toggle betweenthe instructions specific to the pediatric and adult operating modesduring at least one of placing pads on the patient and administering CPRto the patient. In some implementations, a level of the defibrillatingshock is different for the pediatric operating mode and the adultoperating mode. In some implementations, changing the operational modeimmediately prepares the one or more capacitors for the operating modein use. In some implementations, when the operational mode is changedthe one or more capacitors are discharged.

In some implementations, the control comprises a button. In someimplementations, the control comprises the indicator. In someimplementations, the indicator comprises at least one of a visualindicator, a lighted display, an audio indicator, a verbal indicator anda haptic indicator. In some implementations, the one or more computerprocessors are configured to determine at least one of depth and rate ofchest compressions based on a motion signal received arising from chestcompressions applied to the patient.

In some implementations, when the automated external defibrillator is inthe adult operating mode, the one or more computer processors areconfigured to compare the at least one of depth and rate of chestcompressions to a desired range and provide chest compression feedbackto a user. In some implementations, the chest compression feedbackcomprises at least one of visual feedback, audio feedback and hapticfeedback.

In some implementations, the automated external defibrillator can have auser interface configured to provide a visual display of numericalvalues of the determined at least one of depth and rate of chestcompressions when the automated external defibrillator is set to a basiclife support mode. In some implementations, when the automated externaldefibrillator is in the adult operating mode, the one or more computerprocessors are configured to compare the at least one of depth and rateof chest compressions to a desired range and provide chest compressionfeedback to a user. In some implementations, when the automated externaldefibrillator is in the pediatric operating mode, the user interface isconfigured to refrain from providing chest compression feedback to auser.

In some implementations, the one or more computer processors areconfigured to cause the one or more capacitors to be charged to avoltage that is greater when the operating mode is in the adultoperating mode than when the operating mode is in the pediatricoperating mode. In some implementations, the one or more computerprocessors are configured to cause a resistance in a circuit between theone or more capacitors and the patient to be greater when the operatingmode is in the pediatric operating mode than when the operating mode isin the adult operating mode. In some implementations, the one or moreprocessors are configured to analyze one or more portions of the ECGsignal, wherein the analysis differs between the pediatric operatingmode and the adult operating mode.

In some implementations, the automated external defibrillator can haveone or more capacitors for delivering a defibrillating shock to apatient; one or more electronic ports configured to receive signalsindicative of sensed physiological parameters of the patient, and tocommunicate the defibrillating shock to the patient based on a signalproduced from an analysis of the sensed physiological parameters of thepatient; a control for toggling an operating mode of the automatedexternal defibrillator back and forth between a pediatric operating modeand an adult operating mode during a resuscitation process; and anindicator configured to provide an indication of the current operatingmode in use; and one or more computer processors configured to determineif an electrode assembly in communication with at least one of theelectronic ports is usable in at least one or both of the pediatricoperating mode and the adult operating mode.

In some implementations, the one or more computer processors areconfigured to adjust an energy output of the defibrillating shock basedon whether the operating mode is in the pediatric operating mode or theadult operating mode. In some implementations, the control is configuredto change the operating mode when the one or more computer processorsdetermine that the electrode assembly in communication with at least oneof the electronic ports is usable in both the pediatric operating modeand the adult operating mode. In some implementations, the one or morecomputer processors are configured to determine when the electrodeassembly is configured only for the pediatric operating mode, and, inresponse, the indicator automatically indicates the pediatric operatingmode, and the control is disabled. In some implementations, the one ormore computer processors are configured to determine when the electrodeassembly is configured only for the adult operating mode, and, inresponse, the indicator automatically indicates the adult operatingmode, and the control is disabled. In some implementations, theautomated external defibrillator can have a user interface configured toprovide at least one of instructions specific to the pediatric operatingmode and instructions specific to the adult operating mode. In someimplementations, the user interface includes a visual display configuredto provide the at least one of instructions specific to the pediatricoperating mode and instructions specific to the adult operating mode.

In some implementations, the one or more computer processors areconfigured to enter the pediatric operating mode and, in response, causethe user interface to provide the instructions specific to the pediatricoperating mode. In some implementations, when the automated externaldefibrillator is in the pediatric operating mode, the user interface isconfigured to omit chest compression feedback provided to a user. Insome implementations, the one or more computer processors are configuredto enter the adult operating mode and, in response, cause the userinterface to provide the instructions specific to the adult operatingmode. In some implementations, the user interface is configured totoggle between the instructions specific to the pediatric and adultoperating modes during administration of one or more steps ofresuscitation. In some implementations, the one or more computerprocessors are configured to cause the one or more capacitors to becharged to a voltage that is greater when the operating mode is in theadult operating mode than when the operating mode is in the pediatricoperating mode. In some implementations, the one or more computerprocessors are configured to cause a resistance in a circuit between theone or more capacitors and the patient to be greater when the operatingmode is in the pediatric operating mode than when the operating mode isin the adult operating mode.

The techniques described herein may have one or more of the followingadvantages. The AED operating mode can be toggled during operation suchthat it is operating in a mode that is appropriate for treating aparticular patient. The AED can change the treatment given to thepatient depending on the operating mode of the AED. The operating modecan be changed quickly during treatment. The operating mode of the AEDcan be clear to the user. The AED can be used to treat adult patientsand pediatric patients. The AED can display one or more instructionsthat are appropriate for the patient being treated, such as displayinginstructions for treating a pediatric patient when a pediatric patientis being treated and displaying instructions for treating an adultpatient when an adult patient is being treated. The AED can change thefeedback to the user depending on the skill level of the user.

DESCRIPTION OF THE FIGURES

FIG. 1A shows an example of an AED.

FIG. 1B shows an example of a current waveform.

FIG. 1C shows an example of circuitry.

FIGS. 1D-1F show examples of a waveform.

FIG. 2A shows an example of an AED.

FIGS. 2B-13 show examples of instructions provided by an AED

FIG. 14 is a block diagram of an example computer system.

DETAILED DESCRIPTION

Adult and pediatric patients often require different treatments duringdefibrillation therapy. As one example, the defibrillating shock for anadult or relatively large sized individual characteristic of an adultwill involve a greater amount of energy (e.g., could be approximately100 Joules greater) than that for a child or comparatively smallerperson. As provided herein, the term AED refers generically to anydevice or system that is able to provide a defibrillation shock topatients as appropriate for resuscitative treatment. An automatedexternal defibrillator (AED) may have numerous settings which can adjustthe device to accommodate both adult and pediatric patients. In somecases, the procedure for treating the different kinds of patients (e.g.adult and pediatric patients) can vary. A user, who might be using theAED for the first time in an emergency situation, may not be aware ofthe difference in treating different kinds of patients. Hence, thepresent disclosure provides for a defibrillation apparatus (e.g., AED,defibrillator/monitor, etc.) that is configured to operate inpre-configurable modes, for example modes suitable for either adult orpediatric resuscitation. Such an apparatus may include a control that isable to cause the apparatus to dynamically toggle between adult andpediatric operating mode during resuscitation, as well as provide aprominent indication as to which mode the apparatus is currently in.While in a particular mode of operation (e.g., adult, pediatric), themanner in which the apparatus communicates and/or guides the rescuerthrough the resuscitative process may differ appropriately.

An AED can provide different mode-specific user configurations fortreating different kinds of patients. For example, the userconfiguration of the AED may be mode-specific to whether the AED is setto an adult operating mode or a pediatric operating mode. If the AED isoperating in an adult operating mode, the AED can provide instructionsas well as treatment settings for treating an adult. If the AED isoperating in a pediatric operating mode, the AED can provideinstructions as well as treatment settings for treating a pediatricpatient (e.g. a child). As another example of differences in userconfigurations depending upon modes of operation, if the user is anexperienced user or professional responder, the AED can provideinstructions which can be more suitable for the user, for example, byoperating alternatively in either an advanced or basic mode.

In some cases the AED can automatically detect the kind of patient towhich resuscitative treatment is to be applied, for example, byelectrode detection, amongst others. The AED may detect the type ofelectrode connected thereto by any suitable manner, such as for example,via detecting a particular resistor ID associated with the type ofelectrode. In other cases, the user can select the desired operatingmode and the AED will operate according to the selected mode. Suchoperation of the AED can help to ensure that preferred instructions fortreatment can be given to users who may be in position to treat eitheradult or pediatric patients.

FIG. 1A shows an example of an Automated External Defibrillator (AED)100 capable of operating in a pediatric operating mode and an adultoperating mode. The AED 100 has a chassis 110 which houses and protectsthe internal components of the AED 100. The chassis 110 is constructedto provide one or more inputs and outputs, which may include a userinterface. The user interface includes a graphical display 120 which candisplay instructions, treatment feedback, and other information to auser which may be useful for administering resuscitative therapy.

As will be described in more detail below, the user interface of the AED100 has a control 130 for changing the operating mode of the AED 100. Insome implementations, the control 130 can switch the operating modebetween an adult operating mode and a pediatric operating mode. In someembodiments, the control provides the ability for the AED to switchbetween adult and pediatric operating modes dynamically during theresuscitation process. The resuscitation process may include variousactivities performed and/or treatments delivered to a patient during thecourse of resuscitation (e.g. determining the patient's state ofconsciousness, contacting a local emergency number, placing electrodeson the patient, analyzing the patient's ECG, detecting a shockablerhythm, delivering a defibrillation shock, performing CPR, etc.). Forexample, as the rescuer begins resuscitative therapy, the AED may be setto adult operating mode by default, however, it might not be untilfurther into the resuscitation process that the rescuer recognizes thatthe AED should be switched to the pediatric operating mode. Accordingly,the rescuer may switch the AED setting from adult operating mode topediatric operating mode at any time during the resuscitation processand the AED will be able to instantly accommodate the switch andseamlessly continue instructions for the resuscitative process.

The AED 100 has an indicator 135 for providing to the user an indication(e.g., illumination, audible sound, display, etc.) of the currentoperating mode in use. The AED 100 includes a speaker 140. The speaker140 can provide auditory instructions and/or other feedback to a userduring treatment. The AED 100 includes a switch 150 for turning the AED100 into an on or off state. The AED 100 can include a readinessindicator 160 which reports whether the AED 100 needs maintenance orother repair such that it is unfit for current use. The AED 100 caninclude a control, such as a button or switch, for activating treatment,such as a defibrillating shock. In FIG. 1, for example, the control is ashock button 170. The AED 100 includes a port 180. The port 180 canreceive signals from sensors, for example, regarding one or morephysiological parameters of the patient. Such physiological parameters(e.g., ECG signal) may be analyzed by the processor according to anappropriate algorithm to make a determination of whether adefibrillating shock should be administered to the patient. The port 180can communicate signals such as a defibrillating shock. For example, acable leading to defibrillating electrodes can be interfaced with theport 180.

The AED 100 includes several internal components that enable the AED tobe used for defibrillation of multiple kinds of patients. The AEDincludes a computer processor (described in further detail below withrespect to FIG. 14). Among other things, the computer processor can beconfigured to determine in which operating mode the AED should bedelivering treatment.

The computer processor can be configured to determine whether adultelectrodes are connected to the port 180 and subsequently ensure thatthe operating mode of the AED is in the adult operating mode. Forinstance, if adult-specific electrodes (e.g., CPR-D-Padz®, CPRStat-Padz®, Stat-Padz® provided by ZOLL Medical Corp.) are connected tothe AED, the processor may sense that adult-specific electrodes arebeing employed and deactivate the control 130 that would otherwise allowa user to switch the AED from adult operating mode to pediatricoperating mode. Similarly, if the AED is set to pediatric operating modeand adult-specific electrodes are connected to the AED, the processormay then automatically switch the AED to adult operating mode.

The computer processor may also be configured to determine whetherpediatric electrodes are connected to the port 180 and subsequentlychange the operating mode to the pediatric operating mode. For instance,if pediatric-specific electrodes (e.g., Pedi-Padz® provided by ZOLLMedical Corp.) are connected to the AED, the processor may determinethat pediatric-specific electrodes are being employed and automaticallyswitch the AED from adult operating mode to pediatric operating mode.The processor may also deactivate the control 130 so that a user isunable to switch the AED from pediatric operating mode to adultoperating mode as long as the pediatric-specific electrodes areconnected thereto. When the pediatric-specific electrodes are connected,the processor may also transmit a signal so that the indicator 135provides an indication to the user that the AED is in pediatricoperating mode.

The computer processor may be configured to determine whether theelectrode assembly connected to the port 180 is capable of bothpediatric and adult treatment (e.g., Uni-Padz® provided by ZOLL MedicalCorp.) and enable the operating mode to be changed using the control130. In such instances, when the electrode assembly configured for bothadult and pediatric treatment is connected to the AED, the process mayrecognize this capability and allow the control 130 to toggle betweenadult and pediatric operating mode at any point during resuscitation.This process is described in greater detail below.

Other than the computer processor, the internal components of the AEDmay include one or more capacitors. The capacitors can be charged duringuse of the AED. The capacitors can be quickly discharged though anexternal electrode assembly, interfaced with the AED via the port 180,to provide a therapeutic electric shock. The capacitors can discharge insuch a way as to correctly deliver an appropriate electric shock havinga desired level of energy (e.g., pre-configuration default set to120-200 J for an adult patient, 50-85 J for a pediatric patient) to thepatient during treatment. The capacitors can provide electric shock tothe patient at different levels of intensity/energy. The levels ofintensity/energy can be controlled by the computer processor. In someembodiments, the energy configuration of the AED may change betweenadult and pediatric modes, for example, by changing the energy level ofthe defibrillation shock, by controlling the average current deliveredduring the defibrillation shock, etc. Accordingly, the energyconfiguration of the AED may be mode-specific, depending on whether theAED is in the adult operating mode or the pediatric operating mode. Thelevel of defibrillation shock energy is based on the amount of storedcharge provided to the capacitors via a charging current or voltage. Forexample, when storing charge for a defibrillating shock, a greateramount of charge may be stored within the capacitor(s) when the AED isset to adult operating mode as compared to when the AED is set topediatric operating mode. In additional examples, once the capacitor(s)are sufficiently charged, the stored charge is at least partiallydissipated (e.g., by the presence of resistors and/or other dissipatingelement(s) located between the capacitor(s) and the defibrillatingelectrode(s)), so as to reach the desired level of defibrillation shockenergy. For example, a greater resistance may be provided upon dischargewhen the AED is set to pediatric operating mode as compared to when theAED is set to adult operating mode, to reduce the total energy deliveredduring a therapeutic shock than would otherwise be the case. In someexamples, the user can configure the defibrillation shock energy. Insome examples, as discussed herein, the defibrillation shock energy canbe determined by the operating mode of the AED. In additional examples,the defibrillation current delivered to the patient may be controlledduring shock delivery to deliver a current sufficient for defibrillatinga pediatric patient versus that sufficient to defibrillate an adultpatient.

In addition to changing the energy configuration of the AED between anadult and pediatric operating mode, the analysis configuration may alsobe different in the two different mode. That is, the AED may exhibitmode-specific analysis configurations, depending whether the AED is inan adult operating mode or a pediatric operating mode. For example, inthe pediatric operating mode a shock analysis algorithm specific forpediatric patients may be used. The pediatric shock analysis algorithmcan be calibrated to analyze a child's ECG signal rather than an adult'sEGC signal such that the AED can make a more accurate determination ofwhether a shock should be delivered to the pediatric patient. The AEDcan measure the ECG baseline content, QRS rate, width and variability,amplitude, and temporal regularity and determine whether a shockablerhythm exists. For the pediatric patient, one or more of the measuredvalues can be different for a shockable rhythm than for the adultpatient. As another example, in the pediatric operating mode, analysisof data from chest compression sensors and/or ventilation sensors may beadapted for pediatric patients.

Each operating mode of the AED 100 can include various configurations ofthe AED for delivering treatment. The configuration(s) can includehardware settings, software settings, characteristics of treatment,selection of instructions to be delivered to the user, or any othersetting which changes functionality of the AED. In some examples, theoperating mode of the AED can be the configuration which optimizes theAED to deliver treatment to a particular type of patient. Types ofpatients can include, for example, adult patients and pediatricpatients. The AED can be optimized in a number of ways. For example, theuser configuration parameters can be changed between the pediatric andadult operating modes such that the instructions on the display 120 areadjusted for each stage of treatment to be relevant to the pediatricpatient when the AED is operating in pediatric operating mode, orrelevant to the adult patient when the AED is operating in the adultoperating mode. In one example the adult operating mode can be set tothe default user configuration, which can be modified for a pediatricpatient when the pediatric operating mode is enabled.

In some examples, the level of the electric shock delivered can bechanged. Examples of the differences in treatment for adult patients andpediatric patients are further described below and in relation to FIGS.3-13.

In addition to adult and pediatric operating modes, which can beexamples of clinical modes related to treatment of a patient, the AEDcan operation in other non-clinical modes and sub-modes which arerelated non-treatment functionality such as configuration ordiagnostics. For example, the AED can operate in a battery mode, a basicconfiguration mode (e.g., intended for basic life support personnel),and an advanced configuration mode (e.g., intended for advanced lifesupport personnel). The battery mode may be a mode where the AED tests anew battery inserted into the AED. The AED can operate in afully-automatic mode wherein the AED automatically delivers shocktherapy treatment to a patient without waiting for input from the userto deliver the shock. The AED can operate in a semi-automatic modewherein the AED waits for user input to deliver the shock, such as thepress of a button, before the AED delivers shock therapy treatment to apatient. Other sub-modes can include one or more professional modes(e.g., for basic or advanced life support personnel) and anon-professional mode (e.g. a lay-person mode). In various embodiments,when operating in one or more of the professional modes (e.g., basiclife support mode), for example, the AED can display differentinformation to the user who is presumed to be a more sophisticated userthan a typical user. For example, the professional mode include morefeedback regarding the quality of CPR administered to the patient andfewer instructions than in the non-professional mode. In some examples,the AED can initialize to either a professional mode or non-professionalmode by default, depending on pre-configured user settings. Forinstance, the user may desire to configure the AED to initialize inprofessional mode for various reasons, such as location of the AED(e.g., close proximity to basic life support professionals) and/or theintended user of the particular AED. In some examples, the professionalmode can be called a basic life support mode. In some examples, theprofessional mode is a sub-mode of the adult or pediatric operatingmodes, such that when the AED is in adult operating mode, the AED canoperate in a professional mode or non-professional mode. In someexamples, when the AED is in pediatric operating mode, the AED canoperate in a professional mode or non-professional mode.

Various resuscitative treatments can include, for example, any stagerequired for the defibrillation or care of a patient using the AED, suchas initializing the AED, preparing the electrode assembly for use,affixing the electrode assembly to the patient, measuring vitals of thepatient, applying an electric shock, performance and analysis of CPR,and so on. Examples of various stages of treatment are described infurther detail below with respect to FIGS. 3-13.

The chassis 110 of the AED houses and protects the internal componentsof the AED. The corners of the AED can be rounded, truncated, beveled orotherwise structured so that the chassis 110 is free of sharp edges and,hence, may be easy and safe for a person to handle. A handle can beattached to the chassis 110 for the AED to be comfortably andconveniently carried. Various input and output components of the AED canbe flush with the chassis exterior such that the exterior has a smoothand sleek feel/appearance. For example, in FIG. 1, the control 130,speaker 140, and power button 150 are seated in the chassis exteriorsuch that they do not protrude outward from the chassis exterior butrather form depressed features relative to the outer casing surface ofthe chassis.

The chassis can be constructed from any suitable material, such as aplastic or other rigid material. The chassis colors can be chosen suchthat a colorblind user can distinguish labels marking the AED 100 assuch from the chassis. The chassis colors can be chosen to soothe theuser and avoid colors which may induce stress in the user, such asbright red characteristic of warning signs and labels. The chassiscolors can be chosen such that the AED can be recognizable anddistinguishable from other medical devices, which tend to be white,black, and gray. For example, the chassis can be green-yellow and thelabel can be blue.

The AED may have a user interface which includes a display 120. Thedisplay 120 can be a full-color screen, such as a LED-backlit screen.The display 120 can be covered by a touch-sensitive film or other devicesuch that the display 120 has touch-screen functionality. The display120 can be used to show instructions for treatment, warnings, a statusof the AED, or other information which can be relevant to treatment ofthe patient. In some examples, the display 120 can show still images ofinstructions for treatment. In some examples, the display 120 can showanimated instructions for treatment. In some implementations, thedisplay 120 can show real-time or near real-time feedback, measurements,or both based on signals provided from the electrode assembly or othersensors or inputs of the AED.

As noted above, the AED has a control 130 which can be used to changethe operating mode, e.g., pediatric operating mode or adult operatingmode. The control 130 can be easily manipulated by the user to changethe operating mode of the AED during use of the AED. In some examples,the control can be used to change the operating mode of the AED at anytime during use of the AED and/or during the resuscitation process. Forexample, the control 130 can be a button. When the button is depressedby the user, the AED changes its operating mode. For example, the buttoncan dynamically toggle the AED between an adult operating mode and apediatric operating mode. In some implementations, if the electrodes areonly capable of one kind of operating mode then the button can bedisabled from changing the operating mode. Other controls may bepossible, for example, the control may be provided as a switch, touchscreen activation and/or other suitable method.

As described above, the indicator 135 may provide an indication to theuser as to the current mode of operation of the AED 100. The indicatorcan include any method of signaling to the user what the current mode ofoperation is such that the user can perceive the mode of operation atany time during treatment. The indicator 135 can be such that if theuser approaches a scene of treatment after treatment has already begun,the user can immediately (e.g., with little to no delay) determine inwhich mode of operation the AED is currently operating. For instance, asshown, the indicator can be located on the control 130 and/or can be apart of the control 130. In FIG. 1, for example, the indicator isprovided as a pediatric symbol 135 and is located directly on thecontrol 130. When the button is depressed during use of the AED, theindicator 135 illuminates to show that the AED is operating in thepediatric operating mode. The indicator 135 is illuminated whenever theAED 100 is operating in pediatric operating mode. The indicator 135remains free of illumination whenever the AED is operating in the adultoperating mode. In this example, since there are two modes of operation,the illumination of the indicator 135 or the lack of illumination of theindicator 135 is an immediate indication of the operation mode currentlyin use. Some examples of indicators can include a visual indicator suchas illumination of the pediatric symbol as depicted in FIG. 2, an audioindicator such as a tone from the speaker 140, a lighted display such asthe display 120, a verbal indicator such as a verbal instruction fromthe speaker 140, a haptic indicator such as a dial, switch, or otherhaptic indicator, and/or any other suitable manner of indication.

As discussed, each mode of operation for the AED can be different fromother modes of operation. A mode of operation can have one or more of amode-specific series of instructions (e.g. instruction to a user fordifferent stages of treatment), prompts, display images, and treatmentmeasurements, which are described in more detail below. Each mode ofoperation may have a treatment regimen which is appropriate for aparticular class of patient. For example, the AED can have an adultoperating mode of operation which is used for adult patients. In someexamples, the AED has a pediatric operating mode of operation which isused for pediatric patients.

The adult operating mode of operation is used for treatment of adultpatients and may include a user configuration adapted for theresuscitation of adult patients. For example, the AED display 120 mayprovide instructions and feedback information which is suitable fortreatment of the adult patient. As described in more detail below inregard to FIGS. 3-13, during the adult operating mode of operation, thedisplay shows instructions for treatment of the adult patient with theAED. For example, the display shows instructions for preparing the adultpatient for treatment, placing the electrode assembly on the adultpatient, performing CPR on the adult patient, shocking the adult patientwhen appropriate, and any other stages of treatment as well as relevantfeedback from the electrode assembly for each of these stages.

The pediatric operating mode of operation is used for treatment ofpediatric patients and may include a user configuration adapted for theresuscitation of pediatric patients. For example, the AED display 120may provide instructions and feedback information which is suitable fortreatment of pediatric patient. As described in more detail below inregard to FIGS. 3-13, during the pediatric operating mode of operation,the display shows instructions for treatment of the pediatric patientwith the AED. For example, the display shows instructions for preparingthe pediatric patient for treatment, placing the electrode assembly onthe pediatric patient, performing CPR on the pediatric patient, andshocking the pediatric patient when appropriate, as well as relevantfeedback from the electrode assembly for each of these stages.

In addition to having a mode-specific series of images on the display120 for each mode of operation, the AED performs treatment which issuitable for a particular patient. For example, when operating in theadult operating mode, the AED performs treatment which is suitable foran adult patient but might not be suitable for a pediatric patient. Forexample, the level of electric shock set by the AED can be higher fortreatment of an adult patient than the level of electric shock set bythe AED for treatment of a pediatric patient. The AED system may beconfigured to provide escalating rectilinear biphasic defibrillationenergies in varying amounts depending on whether the AED is set to theadult operating mode or the pediatric operating mode. For example, whenset to adult operating mode, in the clinical configuration, therespective defibrillation energies provided by the AED may be 120 J forthe first defibrillation shock, 150 J for the second defibrillationshock and 200 J for the third defibrillation shock; and, when set topediatric operating mode, the respective defibrillation energiesprovided by the AED may be 50 J for the first defibrillation shock, 70 Jfor the second defibrillation shock and 85 J for the thirddefibrillation shock. In various embodiments, for adult or pediatricoperating modes, defibrillation energies provided by the AED may be setaccording to pre-configured defaults or may be set by a user viaconfiguration of the AED during a non-clinical mode. For example, theuser may configure the AED to deliver therapeutic shocks at energylevels other than those noted above, for the adult operating mode and/orpediatric operating mode.

The system may be configured to apply a defibrillating shock accordingto a rectilinear biphasic waveform, such as those administered bydefibrillators provided by ZOLL Medical Corp. Depending on the mode towhich the AED is set (e.g., adult operating mode, pediatric operatingmode), and how the defibrillation(s) may be escalated (e.g., first,second, third shock) the rectilinear biphasic waveform may beadministered so as to exhibit an appropriate level of therapeutic energyto the patient. Illustrative examples of electrotherapy circuits thatmay be suitable for administering a rectilinear biphasic waveform inaccordance with the present disclosure are described in U.S. Pat. No.5,733,310, entitled “Electrotherapy circuit and method for producingtherapeutic discharge waveform immediately following sensing pulse,” andis incorporated by reference herein.

In certain embodiments in accordance with the present disclosure, asshown in FIG. 1B, a biphasic current waveform 101 may include an initialsensing pulse 10, which has an energy lower than that for administeringa therapeutic defibrillating shock. The sensing pulse may allow for thesystem to compensate for variations in patient impedance, so that anappropriate and consistent amount of energy is delivered to the patient.During the initial sensing pulse, the amount of current flowing throughthe patient may be measured for the system to calculate patientimpedance, according to methods known in the art. It can be appreciatedthat such a sensing pulse may be optional, for example, the patientimpedance may be determined significantly prior to discharge of thebiphasic waveform, rather than immediately beforehand. The totalresistance during discharge of the defibrillating shock may be adjusted,so that the total impedance of the system and patient remains relativelyconstant. The sensing pulse is followed by a biphasic defibrillationwaveform having energy sufficient for defibrillating the patient'sheart. As shown, the biphasic defibrillation waveform may include asubstantially rectilinear (linear waveform) positive phase 12 having asawtooth ripple 14, which is in turn followed by a negative phase 16that exhibits an exponential decay until the waveform is truncated. Thepositive phase may optionally include a portion that decreases through aseries of steps 18 through the zero crossing up until the beginning ofnegative phase.

FIG. 1C shows an illustrative embodiment of basic circuitry 102 forproducing a suitable biphasic waveform. A storage capacitor 20 (e.g., asingle capacitor or multiple capacitors connected in series and/orparallel) may be charged to a maximum voltage according to the mode(e.g., pediatric, adult) set by the AED by a charging circuit 22 whilerelays 26 and 28 and the H-bridge are open. The electric charge storedin the storage capacitor 20 may be allowed to pass through electrodes 21and 23 and the body of a patient. Here, relay switches 17 and 19 areopened, and relay switches 26 and 28 are closed. Then, electronicswitches 30, 32, 34, and 36 of H-bridge 48 are closed to allow theelectric current to pass through the patient's body in one direction,after which electronic H-bridge switches 30, 32, 34, and 36 are openedand H-bridge switches 38, 40, 42, and 44 are closed to allow theelectric current to pass through the patient's body in the oppositedirection. Electronic switches 30-44 may be controlled by signalsprovided from a microprocessor 46. Relay switches 26 and 28, which arealso controlled by microprocessor 46, may isolate patient 24 fromleakage currents of bridge switches 30-44.

Electrodes 21 and 23 may be defibrillation electrodes suitable foradministering therapy to an adult and/or pediatric patient, havingsurfaces for placement on the chest of the patient. A resistive circuit50 that includes series-connected resistors 52, 54, and 56 may beprovided in the current path, each of the resistors being connected inparallel with a shorting switch 58, 60, and 62 controlled bymicroprocessor 46. The resistors may exhibit different values ofresistance and any appropriate number of resistors may be employed.During the initial sensing pulse, when H-bridge switches 30, 32, 34, and36 are closed, the resistor-shorting switches 58, 60, and 62 are in anopen state so that the current passes through each of the resistors inseries. Current-sensing transformer 64 senses the current passingthrough the patient 24, from which microprocessor 46 determines theresistance of the patient 24. In various embodiments, rather thanincluding a current-sensing transformer such as that discussed above,the system may include another component for sensing the current, suchas a current-sensing resistor (or other such electrical component)located on either side of the resistor bank.

The initial sensing pulse may be followed by a biphasic defibrillationwaveform, without re-charging of the storage capacitor 20 between theinitial sensing pulse and the biphasic defibrillation waveform. In thisembodiment, if the patient resistance sensed during the initial sensingpulse is low, the resistor-shorting switches 58, 60, and 62 are leftopen at the end of the sensing pulse so that the resistors 52, 54, and56 remain in the current path (the resistors are then successivelyshorted out during the positive phase of the biphasic defibrillationwaveform in the manner described below in order to approximate arectilinear positive phase). The current at the beginning of thepositive first phase 12 of the biphasic defibrillation waveform may bethe same as the current during sensing pulse 10. If the patientresistance sensed during the sensing pulse is high, some or all of theresistor-shorting switches 58, 60, and 62 are closed at the end of thesensing pulse, thereby shorting out some or all of the resistors. Thisleads to an upward jump in current at the end of the sensing pulse.Hence, after the sensing pulse, the biphasic defibrillation waveform hasan initial discharge current that is controlled by microprocessor 46based on the patient impedance sensed by current-sensing transformer 64.

By appropriately selecting the number of resistors that remain in thecurrent path, microprocessor 46 reduces (but does not eliminate) thedependence of peak discharge current on patient impedance, for a givenamount of charge stored by the charge storage device. Such aconfiguration provides for the appropriate amount of energy (based onthe mode to which the AED is set) to be discharged to the patient. Forexample, for a patient resistance of 15 ohms, the peak current may beabout 25 amps, whereas for a patient resistance of 125 ohms the peakcurrent is about 12.5 amps. (a typical adult patient impedance is about75 ohms, whereas a pediatric patient impedance may be less).

During the positive phase of the biphasic waveform some or all of theresistors 52, 54, and 56 that remain in series with the patient 24 aresuccessively shorted out. When one of the resistors is shorted out, thecurrent jumps, resulting in a sawtooth ripple waveform. The ripple mayhave a tendency to be greater in magnitude at the end of the rectilinearphase because the time constant of decay (RC) is shorter at the end ofthe phase than at the beginning of the phase. If all of the resistorshave already been shorted out immediately after the end of the sensingpulse, the positive phase of the biphasic waveform decays exponentiallyuntil the waveform switches to the negative phase.

As is shown in FIG. 1B, at the end of the positive phase, the currentwaveform 101 decreases through a series of rapid steps from the end ofthe positive phase to the beginning of negative phase, one of the stepsbeing at the zero crossing. Microprocessor 46 accomplishes this by 1)successively increasing the resistance of resistive circuit 50 in fixedincrements through manipulation of resistor-shorting switches 58, 60,and 62, then 2) opening the switches in the H-bridge 48 to bring thecurrent waveform down to the zero crossing, then 3) reversing thepolarity of the current waveform by closing the H-bridge switches thathad previously been open in the positive phase of the current waveform,and then 4) successively decreasing the resistance of resistance circuit50 in fixed increments through manipulation of resistor-shortingswitches 58, 60, and 62 until the resistance of resistance circuit 50 isthe same as it was at the end of the positive phase.

A variable resistor 66 may be provided with the other resistors 52, 54,and 56 to reduce the sawtooth ripple. Every time one of the fixed-valueresistors 52, 54, or 56 is shorted out, the resistance of variableresistor 66 may automatically increase to a higher value and thendecrease until the next fixed-value resistor is shorted out. This tends,to some extent, to smooth out the height of the sawtooth ripple, andreduces the need for smaller increments of the fixed-value resistors(i.e., it reduces the need for additional fixed-value resistor stages).

The switches in the left-hand side of H-bridge 48 can be tested byclosing switches 17 and 19, opening switches 26 and 28, closing switches30 and 32, then after a short time closing switches 42 and 44, thenafter a short time opening switches 30 and 32, and then after a shorttime opening switches 42 and 44. If the switches are working properly,current-sensing transformer 64 will sense the passage of current whenall four switches are closed, and will sense no current when switches 30and 32 or switches 42 and 44 are open. Otherwise, current-sensingtransformer 64 will detect the possible presence of a short circuit oran open circuit. Similarly, the switches in the right-hand side ofH-bridge 48 can be tested by closing switches 38 and 40, then after ashort time closing switches 34 and 36, then after a short time openingswitches 38 and 40, and then after a short time opening switches 34 and36. This safety test does not require current to pass through thepatient, due to the placement of current-sensing transformer 64 outsidethe legs of H-bridge 48.

FIG. 1D depicts an example of a rectilinear biphasic waveform 103 basedon a patient impedance of 50 ohms. Here, the microprocessor selects aninitial series-connected resistance of 30 ohms and a residualseries-connected resistance of 0 ohms at the end of the positive phaseof the waveform.

A rectilinear biphasic waveform may be delivered according to differentenergy configurations, depending upon whether an adult or pediatricoperating mode is enabled. For example, the table below providescharacteristics of a rectilinear biphasic waveform when discharged fromthe defibrillator at an energy setting of 200 J, an energy setting thatmay be implemented in an adult operating mode, into patient impedancesof 25 ohms, 50 ohms, 100 ohms and 125 ohms, respectively. For a givenpatient impedance, the first (positive) phase and the second (negative)phase of the waveform may each exhibit a suitable maximum initialcurrent, average current and duration. For example, for an energysetting of approximately 200 J, depending on the measured patientimpedance, the maximum initial current during the first and/or secondphase may be between approximately 10 A and approximately 35 A, and theaverage current during the first and/or second phase may be betweenapproximately 10 A and approximately 30 A.

Discharged Discharged Discharged Discharged into 25 ohm into 50 ohm into100 into 125 load load ohm load ohm load First Phase 32 A 26 A 21 A 17 AMaximum Initial Current First Phase 28 A 22 A 16 A 13 A Average CurrentFirst Phase 6 ms 6 ms 6 ms 6 ms Duration Interphase 150 μsec 150 μsec150 μsec 150 μsec duration between first and second phases Second Phase33 A 19 A 12 A 11 A Maximum Initial Current Second 21 A 14 A 11 A 10 APhase Average Current Second Phase 4 ms 4 ms 4 ms 4 ms Duration

It can be appreciated that other current levels may be possible for thisand other energy settings. The current levels may be adjusted by anysuitable method, for example, via a schedule of resistors as discussedabove. The duration of the first phase may be about 6 milliseconds, theduration of the second phase may be about 4 milliseconds, and theduration in between phases (interphase) may be about 150 microseconds.It may be possible for the first phase, second phase and the timebetween phases to last for other durations of time, as appropriate.

FIG. 1E depicts a graph 104 for an embodiment of a defibrillator thatshows a number of rectilinear biphasic waveforms for a defibrillationdischarge at an energy setting of 200 J, for patient impedances of 25ohms, 50 ohms, 75 ohms, 100 ohms, 125 ohms, 150 ohms and 175 ohms. Insome embodiments, the energy setting of 200 J may correspond to one ormore shocks to be provided when the defibrillator is set to an adultoperating mode configuration. Accordingly, the initial charge and/orschedule of resistors may be adjusted to suit the energy setting. Theripple behavior of the first (positive) phase of the waveform may be dueto resistors that are employed according to a suitable schedule, each ofthe resistors exhibiting a suitable level of resistance. For example,for a patient impedance of 25 ohms, the sequence of resistance may beapproximately 50 ohms, 40 ohms, 30 ohms, 20 ohms and 10 ohms during thefirst phase; and for the second phase, the resistance may beapproximately 10 ohms.

In a pediatric operating mode the energy setting and resistor schedulesmay be optimized for a pediatric patient. For example, FIG. 1F providesa graph 105 for a defibrillator showing rectilinear biphasic waveformsfor a defibrillation discharge at an energy setting of 85 J, for patientimpedances of 25 ohms, 50 ohms, 75 ohms, 100 ohms, 125 ohms, 150 ohmsand 175 ohms. In certain embodiments, the energy setting of 85 J maycorrespond to shocks provided when the defibrillator is set to apediatric operating mode configuration, which is comparatively less thanthe energy setting for the adult operating mode. Similar to thatdiscussed above for the 200 J setting, the energy setting may set thelevel of initial charge and/or schedule of resistors, except resultingin a comparatively lower overall current.

In additional examples changing the mode of the defibrillator may changeother configurations. For example, the AED 100 might provide CPRfeedback that requires a range of chest compression depth for the adultpatient that is different from the corresponding range of chestcompression depth for the pediatric patient. For example, because adultpatients are larger in size than pediatric patients, the recommendedchest compression depth for an adult may be greater than the recommendedchest compression depth for a child. Configurations specific to analysisof the compression parameters and/or configurations providinginstructions to the user may be changed between the modes to be specificto either adult or pediatric patients.

In other implementations the user configurations could be adapted to bedifferent between modes, e.g., when treating a pediatric patient it maybe desirable to limit prompting to aid in delivering chest compressionsat a recommended rate, e.g. by prompts cueing the timing of chestcompressions only, while disabling prompting related to measuring thedepth of compression (which may be more erroneous in pediatricpatients).

The control 130 of the AED 100 can be used to toggle the operating modeof the AED 100 at any time during treatment. For example, when thebutton 130 is pressed, the operating mode of the AED 100 is immediatelytoggled (e.g. with little or no delay perceptible to the user) from onemode to another. The indicator 135 then immediately indicates the newcurrent operating mode. For example, if the operating mode is the adultoperating mode and the button 130 is pressed, the operating modeimmediately toggles to the pediatric operating mode and the indicator135 is illuminated. In some examples, if the operating mode is thepediatric operating mode and the button 130 is pressed, the operatingmode immediately toggles to the adult operating mode and the indicator135 turns off. The display 120 can also immediately toggle between adultand pediatric instructions and images when the control 130 is toggled.In some embodiments, the display 120 may further provide an indicationof the current mode of the AED (e.g., whether the AED is in adult orpediatric operating mode, or in BLS or non-BLS mode).

When the operating mode is toggled, the AED 100 can immediately prepareitself to operate in the desired mode. In one example, the user may wishto toggle the operating mode from the adult operating mode to thepediatric operating mode after the capacitors are charged and ready todeliver a shock at the level appropriate for treatment of the adultpatient. If the user toggles the operating mode to the pediatricoperating mode at this stage of treatment, the AED can discharge thecapacitors without delivering a shock to the patient and recharge thecapacitors to a level appropriate for treating the pediatric patient asquickly as possible for the electronics to safely do so. Conversely, ifthe user toggles the operating mode from the pediatric operating mode tothe adult operating mode after the capacitors are charged and ready todeliver a shock appropriate for treatment of an adult patient, the AEDcan quickly discharge the capacitors without delivering a shock to thepatient and recharge the capacitors to a level appropriate for treatingthe adult patient. Alternatively, when the AED is already charged forpediatric shock delivery and the user toggles the AED from the pediatricoperating mode to adult operating mode, the AED may simply increase thelevel of charge in the capacitor without having to first discharge andthen charge again. Similarly, if the AED is already charged for adultshock delivery and the user toggles the AED from the adult operatingmode to pediatric operating mode, the AED may be configured to decreasethe level of charge in the capacitor to the appropriate level withouthaving to discharge and then charge again. In some examples, when theoperating mode of the AED is toggled at a time when the AED is ready todeliver a shock, the AED 100 can repeat analysis of the patient toensure that the electric shock is still appropriate for treatment. Sincethe operating mode of the AED is able to be changed at any stage oftreatment, the user can ensure that the AED is in the appropriateoperating mode for the patient. For example, if the user accidentallytoggles the operating mode during treatment, the user can immediatelytoggle the operating mode back to the appropriate operating mode withoutlosing a significant amount of time.

The user interface of the AED 100 may include a speaker 140. The speaker140 can provide audio instructions and feedback to the user duringtreatment. The speaker 140 can provide audio of the instructions whichare displayed on the screen so that the user does not have to read thedisplay. For example, audio instructions such as “wait,” “remove shirt,”“apply shock,” and “start CPR” can be provided at the appropriate stagesof treatment. In some examples, the speaker can provide a metronomeduring CPR. The metronome can assist the user in performing chestcompressions by providing pacing sounds to the user during CPR. In someexamples, audio feedback can be provided to the user during treatment.

The AED 100 includes a power button 150 and a readiness indicator 160.The power button can be any control which is used to toggle the AEDbetween an on state and an off state. For example, the power button 150can be a button, switch, dial, or similar. The readiness indicator 160indicates the condition of the AED. For example, the readiness indicator160 can indicate whether the AED is ready to provide treatment orwhether maintenance is needed. For example, in FIG. 1, the readinessindicator 160 displays a check mark when the AED has performed aself-test and is ready for use. When the AED is not ready for use, thereadiness indicator 160 is left blank. For example, the AED may be unfitfor use when the battery is low, the capacitors are damaged, fails aself-test, or any other defect exists which can impact performance orsafety of the AED. If the readiness indicator 160 does not indicate thatthe AED is ready for use, the user should not use the AED

The AED includes a shock button 170. The shock button 170 can be used toapply an electric shock therapy to the patient during treatment. Thesame shock button 170 can be used for both the adult operational modeand the pediatric operational mode. The shock button 170 can have ashock symbol 175 which indicates that the button is for applying theshock to the patient. For example, the shock symbol 175 can be alightning bolt. The shock button 170 can be a different color from therest of the AED. In one example, the shock button 170 can be thedifferent color, such as orange, so that it stands out from the rest ofthe AED, including the other buttons, and is recognizable when depictedon the display 120, such as depicted in FIG. 2B. In some examples, theshock button 170 can be a different size than other controls such thatit is discernable from the other buttons on the AED. In some examples,the shock button 170 can illuminate when the computer processordetermines that shock therapy is recommended. In some examples, theshock button 170 can flash when shock therapy is recommended. Forinstance, when shock is recommended, the shock button 170 may beilluminated or otherwise configured to draw the attention of a rescueruntil it is pressed so that a shock is discharged. Once the shock isapplied, the shock button 170 may then be dimmed or turned off. The useof the shock button is described in further detail below.

The AED has a port 180. The port 180 can be used to interface the AEDwith the electrode assembly or other external sensors which can be usedwith the AED. The port 180 can include both inputs and outputs of theAED. Inputs to the AED can include, for example, ECG waveforms,accelerometer data from a chest compression sensor, impedanceinformation, or other sensor information while treating the patient.Outputs can include, for example, electrical discharge from thecapacitors and other control signals to the electrode assembly orinterfaced sensors.

The computer processor of the AED can use the inputs to determine thestate of the patient and the state of the treatment. For example, thecomputer processor can detect when the cable is unplugged andsubsequently have the AED prompt the user to plug the cable back intothe port 180 to continue treatment. In some examples, the computerprocessor can detect whether electric shock therapy is needed duringtreatment by analyzing the ECG of the patient. In some examples, thecomputer processor can read, interpret, and send for displaymeasurements of a rate and a depth of compressions performed by theuser. In some examples, the computer processor can detect whether theelectrodes of the electrode assembly are suitably affixed to the patientsuch that the shock therapy can be properly administered to the patient.For example, if one or more of the electrodes of the electrode assemblyare improperly attached, the computer processor of the AED can determinethat the pads need to be properly affixed to the patient before theshock therapy can be administered to the patient. In some examples, thecomputer processor can interpret the electrical impedance measured bythe electrodes to make such a determination. The AED can subsequentlyprompt the user to properly affix the pads to the user for treatment asdescribed in greater detail in regard to FIGS. 5-6 below.

The computer processor can use the inputs to determine which operatingmode the AED should operate in for treatment. In one example, if anelectrode assembly which can operate in both adult and pediatricoperating modes is plugged into the port 180, the computer processor canconfigure the AED to toggle between the adult and pediatric operatingmodes when the control 130 is toggled. In some examples, if the computerprocessor detects that an electrode assembly which is plugged into theport 180 is configured only for pediatric or adult use, the computerprocessor can configure the AED to enter the appropriate operating mode(e.g. adult or pediatric operating mode, respectively). In this example,the indicator 135 indicates the current operating mode, such asilluminating for the pediatric operating mode, but the control 130 isdisabled so that the AED remains in the operating mode which iscompatible with the attached electrode assembly even when the control130 is toggled. Such control by the computer processor can assist theuser in treating the patient. For example, the user could be confused asto the whether the attached electrode assembly is configured to treatadult patients, pediatric patients, or both, and the computer processorcan ensure that the AED operates only in the operating modes with whichthe electrode assembly is compatible.

FIG. 2A shows an example of an AED 200 in pediatric operating mode. Theindicator 235 is illuminated. The display 210 shows an example ECGwaveform from the pediatric patient.

As described above, each operating mode of the AED can include one ormore stages of treatment during a resuscitation process. The stages oftreatment can include any step taken before, during, or afterdefibrillation or CPR administration of the patient which are related tothe use of the AED. In some examples, the stages of treatment caninclude one or more of an initialization stage, a configuration stage,an operating mode confirmation stage, a patient preparation stage, anelectrode placement stage, a CPR therapy stage, a shock therapy stage,and a treatment conclusion stage. The stages of treatment are discussedin more detail with respect to FIGS. 2B-13.

FIG. 2B shows an example operating mode confirmation instruction 201.The instruction 201 can be displayed on the display 210 during theoperating mode confirmation stage. The instruction 201 can include oneor more of pictorial instructions, textual instructions, and auditoryinstructions. During the operating mode confirmation stage, if thepatient is a pediatric patient, the user can be prompted to toggle thecontrol 230 if the patient is a pediatric patient. The default state ofthe AED 100 can be configured appropriately. For example, the AED may beconfigured such that the default mode is the mode which may be the mostlikely mode to be used for a particular AED. For example, if the AED islocated in a school or pediatric ward of a hospital, the default modecan be configured to be the pediatric operating mode. In many cases, theAED may be configured so that the default mode is the adult operatingmode. As discussed above, if the computer processor detects that theelectrode assembly only supports a particular operating mode, thecomputer processor can automatically configure the AED to operate in theparticular operating mode and the operating mode confirmation stage canbe skipped. Although the user is instructed to toggle the control duringthe operating mode confirmation stage, the user can toggle the operatingmode by using the control 230 during any stage and can toggle any numberof times between modes. In some examples, the user can also operate theAED without toggling the control 230.

The instruction 201 can include textual instructions on the display 120during the operating mode confirmation stage. The textual instructionscan include “if child, press button,” “if patient is a child, presschild button,” “adult patient selected,” “child patient selected,” orsimilar.

The instruction 201 can include auditory instructions produced from thespeaker 140 during the operating mode confirmation stage. Audioinstructions may be provided as an alternative, or in addition, tovisual or textual instructions. The textual instructions can include “ifchild, press button,” “if patient is a child, press child button,”“adult patient selected,” “child patient selected,” or similar.

As discussed herein, the AED may have mode-specific user configurations,depending on whether the AED is in an adult operating mode and apediatric operating mode. During treatment of a patient, the AED candisplay a mode-specific series of instructions on the display 120. Theoperating mode can determine the specific user configuration, whichincludes mode-specific series of instructions are displayed at eachstage of treatment. For example, when the operating mode of the AED isthe adult operating mode, the mode-specific series of instructions foradult patients is displayed. In some examples, when the operating modeof the AED is the pediatric operating mode, the mode-specific series ofinstructions for the pediatric patient can be displayed. In variousembodiments, the mode-specific series of instructions can be displayedby showing one stage at a time on the display 120. The instruction whichis appropriate for the current stage of treatment can be shown. When thenext stage of treatment is reached, the next instruction in themode-specific series of instructions can be displayed. Although, it canbe appreciated that instructions for multiple stages of the treatmentprocess may also be shown, displayed, or otherwise provided.

The instructions for treatment can be displayed using pictorialrepresentations. In some examples, the pictorial representations caninclude pictures or images of what the treatment should look like forthe current stage. The pictorial instructions can be in color, greyscaleor black and white on the display 120. The instructions can be text. Forexample, the instructions displayed for a stage of treatment can read“expose bare chest,” “attach pads,” “start CPR,” “shock delivered,” andso on depending on the stage of treatment during the resuscitationprocess. In some examples, the display 120 can display both thepictorial instructions and the textual instructions simultaneously for astage of treatment. In some examples, an audio instruction can accompanythe pictorial and textual instructions. As discussed herein, the usercan toggle between the operating modes, and thus the differentmode-specific series of instructions being displayed, at any stage oftreatment.

One or more statistics or information of the treatment can be shownduring any stage. For example, in FIGS. 3-13, the instructions showseveral statistics of the current treatment of the patient. Onestatistic shown in the examples is the lightning symbol of the shockbutton 170 next to a number representing the number of times the shocktherapy has been delivered. For example, when a shock is delivered tothe patient, the number next to the lighting symbol can be incrementedby one. In some examples, a statistic can be a measurement of timeelapsed since the beginning of the treatment, so that a rescuer isbetter able to time the application of appropriate therapies.

Operating the AED for treatment of the patient can have several stagesduring a resuscitation process, which are described in further detailbelow. Once the AED is powered on, the user can check the readinessindicator 160 to determine whether the AED is ready to use. Once the AEDis powered on, the AED can detect what kind of electrode assembly isattached via the port 180 and enter the operating mode which isappropriate. In some examples, the AED can instruct the user how toprepare the patient for treatment with the electrode assembly.

FIGS. 3-4 show examples of an instruction 300, 400 for preparing thepatient (e.g. the patient preparation stage). FIG. 3 shows theinstruction for exposing the bare chest for the mode-specific series ofinstructions for the adult patient. Since each piece of the electrodeassembly can be placed on the chest of the adult patient duringtreatment, the instructions can show that a shirt need not be entirelyremoved from the adult patient. FIG. 4 shows a version of the same stageof instruction for the mode-specific series of instructions for thepediatric patient. For example, the image shows that the shirt of thepediatric patient has been entirely removed from the pediatric patient.During treatment, a piece of the electrode assembly may need to beplaced on the back of the pediatric patient, and so the shirt of thepediatric patient may inhibit treatment if it is not removed by theuser. The images and text of the stage of instructions can beaccompanied by audio prompts. For example, the audio prompt for theadult operating mode instruction of FIG. 3 can include instructions suchas “expose bare chest,” “cut or tear clothing to expose patient's barechest,” or similar text. In some examples, the audio prompt for thepediatric patient mode instruction of FIG. 4 can include theinstructions such as “completely remove the child's shirt, cutting ortearing if needed” or similar instructions.

FIGS. 5-6 show examples of instructions 500, 600 for placement of theelectrode assembly on the patient for different types of patients (e.g.the electrode placement stage). FIG. 5 shows an example of an electrodeplacement instruction 500 from the mode-specific series of instructionsfor the adult patient. The instruction can appear on the display 120.The instruction can appear on the display 120 after the patient has beeninstructed to remove the electrode assembly from a packaging. Thepatient's bare chest is exposed for placement of the electrode assembly.The electrode assembly is removed from packaging and the backing of eachelectrode is removed to expose the adhesive on the bottom surface ofeach electrode. An electrode 501 is placed on the chest of the patient.The electrode 501 can typically be placed on the right side of the adultpatient's chest. The placement of the electrode 501 can be assisted bythe placement of an attached chest compression sensor 520. The chestcompression sensor 520 can have a pattern, such as a dashed cross, on atop surface which guides the user for placing the chest compressionsensor 520 on the adult patient. The chest compression sensor 520 istypically placed in the approximate center of the adult patient'ssternum. The user can orient the pattern on the chest compression sensor520 with an imaginary cross 530 on the adult patient's chest and body.For example, a line can be imagined, drawn from the adult patient's chinto the adult patient's belly button intersecting with a line drawnacross the adult patient's chest to form an approximate cross 530 asshown in FIG. 5. The user can place and orient the chest compressionsensor 520 such that the center or pattern of the sensor approximatelycorresponds with the intersecting point of the cross 530. Such placementcan correspond with where the user will perform chest compressions onthe patient during CPR treatment. The instruction can show text such as“attach pads as shown,” “attach pads to patients bare chest,” orsimilar.

In some examples, if the electrode 501 is attached to the chestcompression sensor 520, the electrode 501 may be automatically orientedto the approximate correct location for treatment on the chest of theadult patient if the chest compression sensor 520 was placed andoriented as described above. In some examples, after the user hasproperly oriented and positioned the chest compression sensor 520 andelectrode 501 on the adult patient's chest, the user can press the chestcompression sensor 520 and electrode 501 into the skin of the adultpatient so that the adhesive affixes the electrode 501 and chestcompression sensor 520 firmly in place. A second electrode 510 isaffixed to the adult patient on an intercostal region. As shown in FIG.5, the electrode 510 can be affixed to a lower left intercostal regionof the adult patient such that the electrode 510 wraps around the leftintercostal muscles. Once the electrodes 501 and 510 have been affixedto the adult patient, the patient may be ready for treatment. If theuser desires feedback on performing chest compressions during CPR, thechest compression sensor 520 can be affixed to the patient as describedabove.

FIG. 6 shows an example of an electrode placement instruction 600 fromthe mode-specific series of instructions for the pediatric patient. Theinstruction can appear on the display 120. The patient's bare chest isexposed for placement of the electrode assembly 100. The electrodeassembly is removed from packaging and the backing of each electrode isremoved to expose the adhesive on the bottom surface of each electrode.An electrode 601 is placed on an intercostal region of the pediatricpatient. As shown in FIG. 6, the electrode 601 can typically be placedon a lower left side of an intercostal region of the pediatric patientsuch that the electrode wraps around the patient's left intercostalmuscles. The placement of the electrode 601 can be assisted by theplacement of an attached chest compression sensor 620. The chestcompression sensor 620 can have a pattern, such as a dashed cross, on atop surface which guides the user for placing the chest compressionsensor 620 on the pediatric patient. The chest compression sensor 620 istypically placed in the approximate center of the pediatric patient'ssternum. The user can orient the pattern on the chest compression sensor620 with an imaginary cross 630 on the pediatric patient's chest andbody. For example, a line can be imagined, drawn from the pediatricpatient's chin to the pediatric patient's belly button intersecting witha line drawn across the pediatric patient's chest to form an approximatecross 630 as shown in FIG. 6. The user can place and orient the chestcompression sensor 620 such that the center or pattern of the sensorapproximately corresponds with the intersecting point of the cross 630.Such placement can correspond with where the user will perform chestcompressions on the patient during CPR treatment. The instruction ofFIG. 6 can include text saying “attach pads to child's back and chest,”“attach pads as shown,” or similar.

In cases where the electrode 601 is attached to the chest compressionsensor 620, the electrode 601 may be automatically oriented to theapproximate correct location for treatment on an intercostal region ofthe pediatric patient if the chest compression sensor 620 was placed andoriented as described above. In some examples, after the user hasproperly oriented and positioned the chest compression sensor 620 andelectrode 601 on the pediatric patient's body, the user can press thechest compression sensor 620 and electrode 601 into the skin of thepediatric patient so that the adhesive affixes the electrode 601 andchest compression sensor 620 firmly in place. A second electrode 610 isaffixed to the pediatric patient on the patient's back. As shown in FIG.6, the electrode 610 is affixed to the approximate center of thepediatric patient's back. Once the electrodes 601 and 610 have beenaffixed to the pediatric patient, the patient may be ready fortreatment. If the user desires feedback on performing chest compressionsduring CPR, the chest compression sensor 620 can be affixed to thepatient as described above.

The first electrode 501, 601, the second electrode 510, 610, and thechest compression sensor 530, 630 can each be represented as a shadedobject in the instructions. The color of the shading for the object canmatch a background color of piece of the electrode assembly representedby the object, such as the first electrode 501, 601, the secondelectrode 510, 610, or the chest compression sensor 530, 630. Therelative shapes and sizes of the objects in the instructions can matchthe shapes, sizes, or both for each piece of the electrode assembly. Theinstructions on the display 120 can match or be consistent withinstructions on the electrode assembly, electrode assembly packaging, orboth. Such consistency can help the user associate the electrodeassembly with the AED and facilitate use of the electrode assembly withthe AED. The instruction can show text such as “place pads as shown” orsimilar.

FIGS. 7-8 show examples of user instructions 700, 800 for performing CPRfor different mode-specific series of instructions, such as the adultand pediatric instructions (e.g. the CPR therapy stage). FIG. 7 shows anexample adult CPR instruction 700 for performing CPR from themode-specific series of instructions for adult patients. The instruction700 can include one or more of pictorial instructions, textualinstructions, and auditory instructions. The instruction 700 can appearon the display 120.

The adult user configuration CPR instruction 700 can include CPRinstructions as one or more pictorial instructions. For example, the CPRinstruction 700, as shown in FIG. 7, shows the approximate handplacement for compressing the adult patient's chest during CPR. Forexample, the instruction 700 shows both the user's hands 710 on thecenter of the adult patient's chest with fingers interlocked. The useris hunched over the patient such that the user can apply compressionforce with the user's full weight. The electrode 720 is visible on theleft side of the intercostals of the adult patient. The color, size, andshape are approximately consistent with the adult instructions forelectrode placement (e.g. as shown in FIG. 5, above). The electrode canbe depicted as faded, discolored or otherwise inconspicuous so as todeemphasize the importance of the electrode during CPR.

The adult CPR instruction 700 shows a compression feedback meter 730.The meter 730 can provide CPR feedback, such as in the form of ananimated measurement, of the user's compression of the chest of theadult patient when the chest compression sensor 530 is present. In oneexample, the meter 730 can be two static bars 733 and a third bar 735.In some examples, the two static bars 733 can represent an approximatesuggested range of compression of the chest of the adult patient. Thesuggested range of chest compression for the adult patient may be setaccording to the most recent American Heart Association Guidelines forCPR (e.g., between 2.0 and 2.4 inches). The third bar 735 can representa measured approximate depth of the compression of the chest of thepatient. Hence, the rescuer may be advised to apply chest compressionssuch that the third bar 735 remains within the region located betweenthe two static bars 733. In some examples, the area above the third bar735 can be shaded to illustrate a bar graph, rather than a single line,for assisting the user in visualizing the approximate measured depth ofthe compression being performed. The three bars can be approximatelyparallel. In an example representation of chest compression, the thirdbar 735 can move within and outside of the range of the two static bars733. For example, when the chest of the adult patient is not compressed,the third bar 735 can be at approximately the same position on thedisplay 120 as the top of the display. When the chest is compressed,then the third bar 735 may move down according to the depth of thecompressions. In some cases, the third bar 735 (or other bars orportions of the display) may be color coded depending on whether thecompressions are within the desired range (e.g., according to AHAguidelines). For instance, when the compressions are within the desiredrange, one or more of the bars or other portions of the screen may becolored green (or another affirmative indicating color), though, whencompressions are outside of the desired range, one or more of the barsor other portions of the screen may be colored red (or another colorindicating an undesirable result). In one example, when the usercompresses the chest of the adult patient, the third bar 735 can movedown the display 120 toward the two static bars, which can provide avisual representation of the depth of the compression performed by theuser. For example, the deeper the chest compression of the adult patientis measured, the lower the third bar 735 can move on the display 120.The meter 730 can change colors when the measured chest compression isoutside the suggested range of chest compression for an adult. Forexample, the meter 730 can be a bright pink or green or other colorindicating an affirmation in CPR performance when the chest compressionsare within the approximate suggested chest compression range. When themeasured chest compressions are out of the suggested range, the meter730 can turn a dark purple, yellow, red or other color indicating thatthe CPR applied needs to change. The chest compression feedback caninclude one or more of visual, auditory, textual, and haptic feedback.In general, CPR feedback may be provided in accordance with the latestAmerican Heart Association (AHA) Guidelines for CardiopulmonaryResuscitation and Emergency Cardiovascular Care.

The adult CPR instruction 700 can show a timer 740. In one example, thetimer 740 can display the time elapsed since initiation of the CPR stageof treatment. Alternatively, the timer 740 may display the amount oftime remaining in the CPR interval. In some examples, the timer 740 cancountdown the appropriate time for the CPR stage of treatment before theuser should progress to another stage of treatment such as ventilation,electric shock therapy or ECG measurement. The display may further showthe elapsed event time (shown in the lower right corner of the figure),indicating the amount of time that has elapsed since the start of rescueand/or when the defibrillator is powered on.

Upon the cessation of chest compressions, the CPR instruction displaymay also show an idle timer, to provide the user with an indication ofthe time elapsed since CPR chest compressions have stopped. When theidle timer shows that a significant amount of time has elapsed, therescuer may be more motivated to apply chest compressions to thepatient. In some embodiments, the device may provide a series ofescalating alerts to the rescuer to continue chest compressions based onhow much time has elapsed as indicated by the idle timer.

The adult CPR instruction 700 can include textual instructions. Textualinstructions on the display 120 can change depending on the measuredcompression depth. For example, the textual instruction can read “pushharder” if the compressions are too shallow, “reduce pressure” if thecompressions are too deep, “good compression,” “increase pace” if thecompressions are being performed too infrequently, “push to match tone,”“open airway,” “check breathing,” “continue CPR,” stop CPR,” “breatheduring CPR,” and so forth.

The adult CPR instruction 700 can include one or more auditoryinstructions. The speaker 140 can provide such instructions. The speaker140 can emit a metronome sound at regular intervals, such as a click,beep, tone, or other sound. The metronome sound can be at a pace thatrepresents an approximate suggested pace (e.g., approximately 100compressions per minute) for providing chest compressions during CPR.The speaker 140 can emit spoken instructions which are relevant to theCPR treatment. For example, the spoken instructions can include “pushharder” if the compressions are too shallow, “reduce pressure” if thecompressions are too deep, “good compression,” “increase pace” if thecompressions are being performed too infrequently, “push to match tone,”“open airway,” “check breathing,” “continue CPR,” stop CPR,” “breatheduring CPR,” and so forth.

FIG. 8 shows an example pediatric CPR instruction 800 that may beincluded in a user configuration corresponding to a pediatric operatingmode. The instruction 800 can include one or more of pictorialinstructions, textual instructions, and auditory instructions. Theinstruction 800 can appear on the display 120.

The pediatric CPR instruction can include one or more pictorialinstructions. For example, the CPR instruction 800, as shown in FIG. 8,shows the approximate hand placement for compressing the pediatricpatient's chest during CPR. For example, the instruction 800 shows oneof the user's hands 810 on the chest of the pediatric patient withfingers spread and the palm in contact with the chest. The user's otherhand can help support the user's weight such that not all of the weightof the user is used to help compress the chest of the pediatric patient.The electrode 820 is visible on the left side of the pediatric patient'sintercostal. The electrode is faded, discolored or otherwiseinconspicuous so as to deemphasize the importance of the electrodeduring CPR.

The pediatric CPR instruction 800 can show a timer 840. In one example,the timer 840 can display the time elapsed since initiation of the CPRstage of treatment. In some examples, the timer 840 can countdown theappropriate time for the CPR stage of treatment before the user shouldprogress to another stage of treatment such as ventilation, electricshock therapy or ECG measurement. Similar to that discussed above withrespect to adult CPR instructions, the CPR instruction may also show anidle timer that appears upon the cessation of chest compressions, whichprovides an indication of the time elapsed since CPR chest compressionshave stopped.

The pediatric CPR instruction 800 can include textual instructions.Textual instructions on the display 120 can change depending on themeasured compression depth. For example, the textual instruction canread “push harder” if the compressions are too shallow, “reducepressure” if the compressions are too deep, “good compression,”“increase pace” if the compressions are being performed tooinfrequently, “push to match tone” “open airway,” “check breathing,”“continue CPR,” stop CPR,” “breathe during CPR,” and so forth. Thepediatric CPR instruction 800 can include one or more auditoryinstructions. For example, the speaker 140 can provide theseinstructions. The speaker 140 can emit spoken instructions which arerelevant to the CPR treatment. For example, the spoken instructions caninclude “push harder” if the compressions are too shallow, “reducepressure” if the compressions are too deep, “good compression,”“increase pace” if the compressions are being performed tooinfrequently, “push to match tone,” “open airway,” “check breathing,”“continue CPR,” stop CPR,” “breathe during CPR,” and so forth. Though,in some implementations, chest compression feedback, such as the abovedescribed textual instruction, meter 730, or other chest compressionfeedback may be omitted from the pediatric CPR instruction 800.Pediatric patients can vary in size (e.g., depending on age) and therecommended chest compression depths can vary such that a suitablerecommendation for chest compression may be difficult to preciselydetermine. In some examples, in the user configuration corresponding tothe pediatric operating mode, the AED can refrain from providing part orall of the chest compression feedback. For example, the AED may provideonly feedback on the timing of chest compressions and refrain fromproviding feedback on compression depth. Yet, when the AED is operatingin the adult operating mode, the user configuration may include chestcompression feedback as discussed above.

The speaker 140 can emit a metronome sound at regular intervals, such asa click, beep, tone, or other sound. The metronome sound can representan approximate suggested pace (e.g., approximately 100 compressions perminute) for providing chest compressions during CPR.

FIGS. 9A-9C show examples a shock therapy cycle. FIG. 9A shows anexample of an analyzing instruction 900 for the mode-specific series ofinstructions for the adult patient. The instruction 900 can include oneor more of pictorial instructions, textual instructions, and auditoryinstructions. The instruction 900 can appear on the display 120. Forexample, the analyzing instruction 900 can display while the AED 100measures the adult patient's ECG signal to determine whether to preparethe AED to deliver an electric shock to the patient through theelectrode assembly. The user 910 is shown to be away from the adultpatient 920 such that the user is not in contact with the adult patient.The user 910 can be advised not to contact the patient 920 while thepatient's ECG signal is being analyzed to determine whether a shockableor non-shockable ECG rhythm exists. In some examples, it is possible forsuch contact to disrupt the measurement of the patient's ECG signal. Theuser 910 can be shown with his hands up and away from the patient 920.The electrode 930 is visible on the adult patient's abdomen. The color,size, and shape are approximately consistent with the adult instructionsfor electrode placement (e.g. as shown in FIG. 5, above). The electrodecan be represented inconspicuously so as to deemphasize the importanceof the electrode during the analyzing stage of treatment.

The analyzing instruction 900 can include textual instructions. Textualinstructions which are relevant to the analyzing stage can appear on thedisplay 120 and can change depending on the measured vitals. Forexample, the textual instruction can read “don't touch patientanalyzing” during analysis, “re-attach electrodes” if the electrodesdetatch from the patient, “plug in pads cable” if the cable detatchesfrom the port 180, “shock advised,” “no shock advised,” “checkresponsiveness,” “call for help,” and so forth.

The analyzing instruction 900 can include one or more auditoryinstructions. The speaker 140 can provide such instructions. The speaker140 can emit spoken instructions which are relevant to the analyzingstage of treatment. For example, the textual instruction can read “don'ttouch patient analyzing” during analysis, “re-attach electrodes” if theelectrodes detatch from the patient, “plug in pads cable” if the cabledetatches from the port 180, “shock advised,” “no shock advised,” “checkresponsiveness,” “call for help,” and so forth.

FIG. 9B shows an example of an analyzing instruction 901 for themode-specific series of instructions for the pediatric patient. Theinstruction 901 can be similar to the instruction 900, though apediatric patient 921 is depicted rather than an adult patient (e.g.,the adult patient 920 shown in FIG. 9A). The instruction 901 can includeone or more of pictorial instructions, textual instructions, andauditory instructions which are similar to the adult analysisinstructions 900. The electrode 931 is visible on the left side of thepediatric patient's The color, size, and shape are approximatelyconsistent with the pediatric instructions for electrode placement (e.g.as shown in FIG. 6, above). intercostal. The color, size, and shape areapproximately consistent with the pediatric instructions for electrodeplacement (e.g. as shown in FIG. 6, above). The electrode isinconspicuously shown and can be represented as faded as to deemphasizethe importance of the electrode during the analyzing stage of treatment.

FIG. 9C shows an example of an alternative analyzing instruction 902 forthe analysis stage. The instruction 902 can be displayed in anyoperating mode, such as the pediatric operating mode and the adultoperating mode. In the example of FIG. 9C, a symbol, such as a heart904, is displayed which has a cursor 905 nearby. In some examples, thecursor 905 can be animated. For example, the cursor can move around theheart 904 to indicate to the user that the AED is analyzing thepatient's ECG, processing the results, or otherwise performing analysis.The instruction 902 can include one or more of pictorial instructions,textual instructions, and auditory instructions which are similar to theadult analysis instructions 900 and the pediatric analysis instructions901.

In some implementations, a voting scheme can be employed to determinethe presence or absence of shockability. A voting scheme usesfixed-length time segments. For example, data corresponding to threeseparate segments of ECG data can be processed to label the segments aseither shockable or non-shockable, and the final decision can be basedon the labels corresponding to at least two of the three labels. If thefirst two segments are labelled as shockable, the voting scheme can beterminated and the presence of a shockable rhythm can be identified. Ifthe first segment is labelled as shockable and the second is labeled asnon-shockable, a third segment is evaluated. In such a voting scheme,each segment is typically of fixed length, e.g., three seconds. Thus,when only using such a voting scheme, a minimum amount of time elapsesbefore a determination can be made of whether a patient is in ashockable or non-shockable state. For example, if three-second segmentsare used, at least six seconds, and up to nine seconds, elapses before adetermination can be made.

In contrast, in some implementations, the delay inherent in a votingscheme can be avoided, for example, by using high-accuracy clauses indetermining the presence or absence of shockable rhythm. A clause is anexpression that defines constraints on features of an ECG waveformunderlying the ECG data; a clause is said to be met (or satisfied) ifthe criteria of the clause are met by the features of the ECG waveformbeing analyzed. In particular, if the criteria are met, then the ECGrhythm is said to be shockable or non-shockable, depending on theparticular clause. High accuracy (e.g., low false positive rate) clausesmay be created or defined in various ways. Using such high accuracyclauses can allow for identifying the presence or absence of shockablerhythms within a short time window (e.g., less than one second) therebyreducing analysis time as compared to, for example, the analysis timeassociated with a voting scheme. In some implementations, thehigh-accuracy clauses are determined heuristically by testing variouscandidate clauses for accuracy against a database of pre-stored patientdata to determine clauses that have low false positive rates. In someimplementations, the clauses can be determined, for example, by using amachine learning process on the database to identify conditions thatindicate the presence of shockable rhythms with low false positiverates.

A clause that applies to an adult patient may be inapplicable to apediatric patient and vice-versa. For example, because a pediatricpatient typically has a higher heart rate than an adult patient, thecharacteristics of a pediatric patient's ECG waveform will be differentthan an adult patient's. Thus, a different set of clauses may be usedwhen a defibrillator is in a pediatric operating mode versus an adultoperating mode. In this way, the analysis of the ECG signal differs whenin the pediatric operating mode versus an adult operating mode. Further,while the voting scheme described above can be applied to both pediatricpatients and adult patients, in some implementations, the technique ofusing high accuracy clauses is typically only applied to adult patients(e.g., used in an adult operating mode).

Although the use of high-accuracy clauses tends to be faster than theuse of a voting scheme, a voting scheme can still be used in certainsituations, e.g., situations in which none of the high accuracy clausesare met and thus cannot be used in making the determination of whether apatient is in a shockable or non-shockable state. For example,normal-accuracy clauses may be used with the voting model describedabove.

The clauses with a sufficient level of accuracy for a particular timesegment length (“high accuracy” clauses), as well as clauses with aninsufficient level of accuracy for a particular time segment length(“normal accuracy”) are defined with parameters that are calculated byprocessing ECG data stored in a memory buffer.

In some examples, high accuracy clauses are defined as having a accuracythreshold of 99% for a particular time length (width) of a waveform. Inother words, if a clause is associated with a time length of 3 secondsand has an accuracy of at least 99%, the clause is a high accuracyclause.

In some examples, a particular clause is a high accuracy clause if theclause is applied to a portion of an ECG signal meeting a threshold timelength (e.g., a length associated with the particular clause) needed toachieve a certain level of accuracy. Further, the same clause may be anormal accuracy clause if the clause is applied to a portion of an ECGsignal that does not meet the threshold time length, e.g., the portionof the ECG signal has a length less than the threshold. In this way, asthe length of the ECG signal portion increases, accuracy tends toincrease as well. Thus, there will be a minimum time segment lengthbelow which a clause is only a normal accuracy clause, and is notsuitable as a high accuracy clause, but for time segment lengths longerthan this minimum time length, the clause is a high accuracy clause.

For instance, there may be clauses for which the minimum time segmentlength is 1 second, which are termed “1-second clauses.” For instance,there may be clauses for which the minimum time segment length is 2seconds, which are termed “2-second clauses.” For instance, there may beclauses for which the minimum time segment length is 3 seconds, whichare termed “3-second clauses.” Segments for which the minimum timelength is 6 seconds are termed “6-second clauses”. Some examples ofthese are listed in Table 1.

TABLE 1 Clause Intended Timing Waveforms Clause Logic Result 1 secondNormal sinus rhythm Maximum_slope >200 uv/sample No Shock (one clearpeak) and relative_flatness >100 1 second Asystole (low maxMax_amplitude <50 uv and No Shock and min amplitudes) Min_amplitude <−50uv 1 second Slow VT Peaks <3 and No Shock average_peak_width >160 ms 1second PEA Maximum_slope <30 uv/sample No Shock and peaks <3 1 secondVFIB Peaks >3 and relative_flatness <50 Shock 1 second Fast VT Peaks >=4and Shock average_peak_width >160 ms and peak_width_variability <100 2AFIB (many peaks Maximum_slope >200 uv/sample No Shock seconds but oneor more tall and relative_flatness >80 and peaks)peak_tops_amplitude_variability <250 2 Slow PEA Maximum_slope <50uv/sample seconds and peak_tops_amplitude_variability <250 No Shock andpeak_tops_interval_variablity <100 2 VF (many peaks) Maximum_slope >50uv/sample Shock seconds and relative_flatness <50 andslope_zero_crossings >20 seconds VT (high rate and R-R_interval <350 msand Shock VT QRS_Width >140 ms and QRS_Width_Variation ==1 6 VT waveform(HR > R-R_interval <400 ms and Shock seconds 150 bpm and wideQRS_Width >140 ms and complexes) QRS_Width_Variation ==1 and flatness<50 6 irregular PEA flatness >200 and No Shock seconds rhythm(intermittent pos_peak_width >300 flat areas and wide peaks)

Some additional 3-second clauses are found in Table 2.

TABLE 2 Intended Waveforms Clause Logic Result Few sharp ((AmplitudeVariability < Threshold) AND No Shock peaks (Amplitude >250 microvolts)AND (Maximum Slope > Threshold)) Stable HR and ((QRS Rate >220) AND(Width Variation == No Shock QRS width Stable) AND (Width <100milliseconds)) OR ((SVT) AND (QRS Rate >245)) Stable QRS ((WidthVariation == Stable) AND (QRS No Shock width Width <65) AND(Amplitude >250) AND (QRS Rate >300) Stable QRS ((Amplitude Variability< Threshold) AND No Shock amplitude, (Amplitude >500) AND (Amplitudelarge QRS Variability <= Threshold) AND (QRS amplitude, Variability <Threshold) AND clear peaks. (QRS Rate >300) HR >180

Some additional 6-second clauses can be found in Table 3.

TABLE 3 Intended Waveforms Clause Logic Result Asystole (Averageamplitude less than 100 microvolts) No waveform Shock with very smallelectrical activity Fast PEA (QRS Rate greater than 270 BPM) AND (QRS Notype Variability < QRSV_Threshold) AND Shock waveform (AmplitudeVariability < AV_Threshold) AND where (Maximum Slope <Min_Slope_Threshold) HR >160 AND (Width Variability > WV_Threshold) withsome variability and stable QRS width but maximum slope is low SVT type((SVT Beats Detected) OR No waveform, ((NUMBER_OF_SVT_BEATS > ShockNumber SVT_CNT_Threshold) AND (QRS_Rate > of SVT QRS_Rate_Threshold) AND(QRS_Width < beats QRSW_Threshold)) OR exceeds ((NUMBER_OF_SVT_BEATS >threshold, SVT_CNT_Threshold) AND (QRS Rate > QRS heart Rate Threshold2) AND (QRS_Width < QRS rate <185, Width Threshold)) QRS width <140 ms

In a typical scenario, a caregiver applies electrodes of a defibrillatorto a patient. The defibrillator then collects ECG data, sometimesconcurrent with a CPR treatment applied to the patient by the caregiver,or at times upon completion of a CPR treatment cycle or in between CPRtreatment cycles. The defibrillator collects and processes ECG data byevaluating clauses against time segments of the collected data. If atleast one high-accuracy clause is met, the defibrillator uses the stateindicated by the clause (e.g., shockable or non-shockable) to direct thecaregiver, or the defibrillating device itself, to administer a shock.In some implementations, in an adult operating mode, a shockable statemay be identified in less than 6 seconds and sometimes within 2-3seconds, within 1 second or less of the patient entering the state basedon results of applying the clauses to the time segments of data. Othertimes, a three-step voting scheme employing fixed-length time segmentspredetermined prior to analysis is used, which may take at least 6-9seconds or more to identify the patient's current state. In someimplementations, a pediatric operating mode only uses the three-stepvoting scheme.

In some examples, the caregiver may halt the CPR treatment (e.g., due toexpress instruction to halt CPR treatment, during the natural course ofrepetitive CPR treatment, and/or during ventilations) while some of thedata after completion of CPR treatment is being collected and analyzedfor further confirmation of an initial determination of whether therhythm is shockable or not shockable. Confirmation of an initialdetermination of shockability is sometimes referred to as areconfirmation mode which may allow for filtered, eliminated orotherwise reduced CPR artifact in the signal during analysis, but it maypose a potential danger to the patient depending on how long the CPRtreatment is halted. Thus, if the evaluation of clauses against timesegments of the data is successful in determining the state of thepatient after a relatively short amount of time, e.g., less than 6seconds, the CPR treatment can resume relatively quickly, reducing riskto the patient. In some examples, reconfirmation mode is only availablefor adult patients, e.g., only available in an adult operating mode.

FIGS. 10A-10D and FIG. 11 show examples of instructions during the shocktherapy stage of treatment. During the shock therapy stage, thecapacitors can charge to a specified energy level (e.g. a voltage). Whenan electric shock is desired, the capacitors can discharge through theelectrode assembly such that current can pass between the electrodes ofthe electrode assembly. The specified energy level can be different fordifferent patients. In some examples, the pediatric patient can requirea lower energy level than the adult patient.

FIG. 10A shows an example of an instruction 1000 displayed if anelectric shock is recommended. The instruction can be shown on thedisplay 120 and can include pictorial, textual, and auditoryinstructions. In some examples, the instruction can include a bright,vibrant color (e.g. orange, red, or similar). In some examples, thebright vibrant color can match the color of the shock button 170 suchthat the user can associate the shock button 170 with the instruction1000. The bright vibrant color can serve as a warning to the user toproceed with caution. The instruction 1000 can include a large arrow1010. The large arrow 1010 can be animated. For example, the arrow canmove in a downward motion to suggest a pressing motion. In someexamples, the instruction 1000 is skipped and the AED can automaticallybegin a countdown to electric shock.

The instruction 1000 can include textual instructions. For example, thetextual instruction can advise a user to “press flashing shock button,”“press shock button,” “press shock button semi,” “press shock buttonfully,” or the like. The textual instruction can be delivered inauditory form, as discussed above.

FIGS. 10B-10D show examples of a countdown during the electric shocktherapy stage. In some examples, once the shock button has been pressed,the instructions in FIGS. 10B-10D can be shown in sequence to count downto the moment when the electric shock can occur. In some examples, thecountdown can begin immediately once the computer processor determinesthat the electric shock is recommended. The countdown can serve as asafety measure such that the user is not accidentally shocked by the AEDwhen handling the electrode assembly. The instructions can include largenumerical digits 1020 which decrease in value in subsequentinstructions. For example, the AED can countdown from three to two toone before shocking. The numerical digits 1020 can be accompanied by theshock symbol 1175. The shock symbol 1175 can match a symbol on the shockbutton 170. The shock symbol can be a symbol which connotes arelationship to electricity, such as a lightning bolt. In some examples,the countdown can be halted for various reasons, such as the padsdisconnecting, AED malfunction, an abort by the user, and so on. If thecomputer processor detects that the electrode assembly has detached fromthe patient or is improperly configured, the AED may return to theelectrode assembly configuration stage.

In some examples, once the countdown is completed the AED can administerthe electric shock. In some examples, the electric shock can be appliedimmediately when the shock button 170 is pressed. Once the electricshock has occurred, a confirmation screen 1100 can be displayed. Anexample of the confirmation screen is shown in FIG. 11. A checkmark 1110or other confirmatory symbol can be displayed. The confirmation caninclude a textual confirmation, such as “shock delivered, shockcomplete,” and so forth. The AED can then repeat one or more stages oftreatment as needed.

FIG. 12 shows an example of a professional adult CPR instruction 1200.In some examples, the instruction can be shown on the display 120 whenthe AED is configured to be in professional mode. In some examples, theprofessional mode can be called a basic life support mode, for personneltrained in basic life support protocols. The instruction can be intendedfor a more experienced user, such as a professional responder or thosetrained in advanced life support protocols. The instruction 1200 can bemore complex and include more feedback than the correspondinginstruction in a non-professional (e.g. lay person) mode, so that theprofessional is better able to assess the rescue performance. Forexample, an ECG scale marker 1210 measured by the AED can be displayedto the professional responder or user.

In some examples, numerical measurements of one or more of compressiondepth, rate, and time can be displayed. For example, a chest compressiondepth reading 1220 in centimeters can replace the compression feedbackmeter 730. Numerical readings could confuse or distract anon-professional and so can be reserved for professional users. Though,because professional users may often be trained based on numericalvalues for chest compression, it may be preferable for professionalusers to view actual numbers to determine the quality of chestcompressions that are provided. In some implementations, a chestcompression rate number 1250 and a CPR countdown timer 1240 can bedisplayed. A user prompt can be displayed. For example, a text 1230reading “Good Compressions” can be displayed to the user when the useris giving proper compressions to the patient. A number of shocksdelivered 1260 to the patient can be displayed.

The professional mode instructions can be distinguished from thenon-professional instructions such that it is quickly apparent in whichmode the AED is operating. In some examples, the professional modeinstructions each have a black background. As with the non-professionalinstructions, professional instructions can include pictorial, textual,and auditory instructions and feedback. In some cases, the display orother portion of the device may provide an indicator for informing auser of the current operational mode of the device. For example, when inBLS mode, the display might show a textual or graphical representationof the operational mode, such as “BLS,” or a checkbox that is marked orunmarked to indicate whether the device is set to BLS mode, or anotherode.

As discussed above, depending on the mode of operation to which thedevice is set, the type of chest compression feedback may vary. Forexample, when the device is operating in BLS mode and adult operatingmode, the display may show numerical values of depth and rate of chestcompressions, and the device may further provide CPR feedback, such asprompts for the rescuer to adjust the manner in which chest compressionsare applied, for example, by pushing harder, pushing deeper, pushingsofter, pushing faster, pushing slower, fully releasing from the chest,amongst others. Though, when the device is operating is operating in BLSmode and pediatric operating mode, the display may show numerical valuesof depth and rate of chest compressions, however, in variousembodiments, because the preferred ranges of CPR feedback for childrencan vary widely from person to person, no CPR feedback prompting isprovided. Although, in some embodiments, even if the device is set inpediatric operating mode, it may be possible to provide an appropriatelevel of CPR feedback prompting. As further depicted, the professionalmode display provides other information. For example, the display mayshow a CPR countdown timer indicating the amount of time remaining inthe CPR interval; an indication of the amount of time that has elapsedsince the start of rescue or when the device has been powered on; andthe number of defibrillation shocks that have been provided to thepatient during rescue. The display may also show the ECG rhythm of thepatient. The ECG rhythm provided on the display may be a raw ECG rhythmas detected by the electrodes or, in some cases, the ECG rhythm shown onthe display may be a processed ECG rhythm that accounts for and filtersout artifacts due to chest compressions.

FIG. 13 is example of a display during a professional mode where shocktherapy is delivered. As with FIG. 12, the instruction can be intendedfor a more experienced user, such as a professional responder. In someexamples, the professional mode can be called a basic life support mode.The instructions provided in this mode can be more complex and includemore feedback or information than the corresponding feedback orinformation provided in a non-professional (e.g. lay person) mode. Forexample, an ECG 1310 measured by the AED can be displayed to theprofessional responder or user. In some examples, in the basic lifesupport mode, numerical measurements of one or more of compressiondepth, rate, and time can be displayed.

FIG. 14 is a block diagram of an example computer system 1400. Forexample, referring to FIG. 1A, the AED is in the pediatric and/or adultsetting. While in the professional mode, the device may also 100 couldbe an example of the system 1400 described here. The system 1400includes a processor 1410, a memory 1420, a storage device 1430, and oneor more input/output interface devices 1440. Each of the components1410, 1420, 1430, and 1440 can be interconnected, for example, using asystem bus 1450.

The processor 1410 is capable of processing instructions for executionwithin the system 1400. The term “execution” as used here refers to atechnique in which program code causes a processor to carry out one ormore processor instructions. In some implementations, the processor 1410is a single-threaded processor. In some implementations, the processor1410 is a multi-threaded processor. In some implementations, theprocessor 1410 is a quantum computer. The processor 1410 is capable ofprocessing instructions stored in the memory 1420 or on the storagedevice 1430. The processor 1410 may execute operations such as readinginput data, determining levels of electric shock therapy, and otherfunctions described in more detail above.

The memory 1420 stores information within the system 1400. In someimplementations, the memory 1420 is a computer-readable medium. In someimplementations, the memory 1420 is a volatile memory unit. In someimplementations, the memory 1420 is a non-volatile memory unit.

The storage device 1430 is capable of providing mass storage for thesystem 1400. In some implementations, the storage device 1430 is anon-transitory computer-readable medium. In various differentimplementations, the storage device 1430 can include, for example, ahard disk device, an idle timer optical disk device, a solid-statedrive, a flash drive, magnetic tape, or some other large capacitystorage device. In some examples, the storage device may store long-termdata, such as ECG readings, chest compression information, or other dataas shown in FIG. 1A. The input/output interface devices 1440 provideinput/output operations for the system 1400. In some implementations,the input/output interface devices 1440 can include one or more of anetwork interface devices, e.g., an Ethernet interface, a serialcommunication device, e.g., an RS-232 interface, and/or a wirelessinterface device, e.g., an 802.11 interface, a 3G wireless modem, a 4Gwireless modem, etc. In some implementations, the input/output devicecan include driver devices configured to receive input data and sendoutput data to other input/output devices, e.g., keyboard, printer anddisplay devices 1460. In some implementations, mobile computing devices,mobile communication devices, and other devices can be used.

Referring to FIG. 1A, operation of the AED can be realized byinstructions that upon execution cause one or more processing devices tocarry out the processes and functions described above, for example,treating the adult or pediatric patient. Such instructions can include,for example, interpreted instructions such as script instructions, orexecutable code, or other instructions stored in a computer readablemedium.

In some examples, the system 1400 is contained within a singleintegrated circuit package. A system 1400 of this kind, in which both aprocessor 1410 and one or more other components are contained within asingle integrated circuit package and/or fabricated as a singleintegrated circuit, is sometimes called a microcontroller. In someimplementations, the integrated circuit package includes pins thatcorrespond to input/output ports, e.g., that can be used to communicatesignals to and from one or more of the input/output interface devices1440.

Although an example processing system has been described in FIG. 14,implementations of the subject matter and the functional operationsdescribed above can be implemented in other types of digital electroniccircuitry, or in computer software, firmware, or hardware, including thestructures disclosed in this specification and their structuralequivalents, or in combinations of one or more of them. Implementationsof the subject matter described in this specification, such as storing,maintaining, and displaying artifacts can be implemented as one or morecomputer program products, i.e., one or more modules of computer programinstructions encoded on a tangible program carrier, for example acomputer-readable medium, for execution by, or to control the operationof, a processing system. The computer readable medium can be a machinereadable storage device, a machine readable storage substrate, a memorydevice, or a combination of one or more of them.

The term “system” may encompass all apparatus, devices, and machines forprocessing data, including by way of example a programmable processor, acomputer, or multiple processors or computers. A processing system caninclude, in addition to hardware, code that appears when chestcompressions have prematurely ceased. The idle timer may provide theuser with an indication of the time elapsed since CPR chest compressionshave stopped, so creates an execution environment for the computerprogram in question, e.g., code that the rescuer may know whether anappreciable amount of time have elapsed without chest compressions.Accordingly, the rescuer may be more encouraged to apply chestcompressions to the patient as the idle timer continues to appear and/ordisplay long idle times. constitutes processor firmware, a protocolstack, a database management system, an operating system, or acombination of one or more of them.

A computer program (also known as a program, software, softwareapplication, script, executable logic, or code) can be written in anyform of programming language, including compiled or interpretedlanguages, or declarative or procedural languages, and it can bedeployed in any form, including as a standalone program or as a module,component, subroutine, or other unit suitable for use in a computingenvironment. A computer program does not necessarily correspond to afile in a file system. A program can be stored in a portion of a filethat holds other programs or data (e.g., one or more scripts stored in amarkup language document), in a single file dedicated to the program inquestion, or in multiple coordinated files (e.g., files that store oneor more modules, sub programs, or portions of code). A computer programcan be deployed to be executed on one computer or on multiple computersthat are located at one site or distributed across multiple sites andinterconnected by a communication network.

Computer readable media suitable for storing computer programinstructions and data include all forms of non-volatile or volatilememory, media and memory devices, including by way of examplesemiconductor memory devices, e.g., EPROM, EEPROM, and flash memorydevices; magnetic disks, e.g., internal hard disks or removable disks ormagnetic tapes; magneto optical disks; and CD-ROM, DVD-ROM, and Blu-Raydisks. The processor and the memory can be supplemented by, orincorporated in, special purpose logic circuitry.

1. An automated external defibrillator comprising: one or morecapacitors for delivering a defibrillating shock to a patient; one ormore electronic ports configured to receive signals indicative of sensedphysiological parameters of the patient, and to communicate thedefibrillating shock to the patient based on a signal produced from ananalysis of the sensed physiological parameters of the patient; one ormore capacitors for delivering a defibrillating shock to a patient; oneor more electronic ports configured to receive signals indicative ofsensed physiological parameters of the patient, and to communicate thedefibrillating shock to the patient based on a signal produced from ananalysis of the sensed physiological parameters of the patient; acontrol configured to switch between a pediatric operating mode and anadult operating mode, wherein each operating mode comprises amode-specific energy configuration and a mode-specific userconfiguration; an indicator configured to provide an indication of theoperating mode in use during a resuscitation process; one or moreprocessors configured to switch to the mode-specific energyconfiguration and the mode-specific user configuration upon a change ofoperating mode between the pediatric operating mode and the adultoperating mode such that the automated external defibrillator delivers athe defibrillating shock to a patient based on the mode-specific energyconfiguration; and a user interface that provides resuscitationinstructions to a user based on whether the mode-specific userconfiguration is in the pediatric operating mode or the adult operatingmode.
 2. The automated external defibrillator of claim 1 wherein thecontrol is further configured to switch by toggling the operating modeof the automated external defibrillator back and forth between thepediatric operating mode and the adult operating mode.
 3. The automatedexternal defibrillator of claim 2 wherein the control is furtherconfigured to switch the operating mode when the one or more computerprocessors determine that the electrode assembly in communication withat least one of the electronic ports is usable in both the pediatricoperating mode and the adult operating mode.
 4. The automated externaldefibrillator of claim 1 wherein the one or more computer processors areconfigured to determine when the electrode assembly is configured onlyfor the pediatric operating mode, and, in response, the indicatorautomatically indicates the pediatric operating mode, and the control isdisabled.
 5. The automated external defibrillator of claim 1 wherein theone or more computer processors are configured to determine when theelectrode assembly is configured only for the adult operating mode, and,in response, the indicator automatically indicates the adult operatingmode, and the control is disabled.
 6. (canceled)
 7. The automatedexternal defibrillator of claim 1 wherein the user interface includes avisual display configured to provide the at least one of instructionsspecific to the pediatric operating mode and instructions specific tothe adult operating mode.
 8. The automated external defibrillator ofclaim 1 wherein the one or more computer processors are configured toenter the pediatric operating mode and, in response, cause the userinterface to provide the instructions specific to the pediatricoperating mode.
 9. The automated external defibrillator of claim 8wherein, when the automated external defibrillator is in the pediatricoperating mode, the user interface is configured to omit chestcompression feedback provided to a user.
 10. The automated externaldefibrillator of claim 1 wherein the one or more computer processors areconfigured to enter the adult operating mode and, in response, cause theuser interface to provide the instructions specific to the adultoperating mode.
 11. The automated external defibrillator of claim 1wherein the user interface is configured to toggle between theinstructions specific to the pediatric operating mode and theinstructions specific to the adult operating mode when the control isused to toggle between the modes.
 12. The automated externaldefibrillator of claim 11 wherein the user interface is configured totoggle between the instructions specific to the pediatric and adultoperating modes during administration of one or more steps ofresuscitation.
 13. The automated external defibrillator of claim 12wherein the user interface is configured to toggle between theinstructions specific to the pediatric and adult operating modes duringat least one of placing pads on the patient and administering CPR to thepatient.
 14. The automated external defibrillator of claim 1 wherein alevel of the defibrillating shock is different for the pediatricoperating mode and the adult operating mode.
 15. (canceled)
 16. Theautomated external defibrillator of claim 1 wherein when the operationalmode is changed the one or more capacitors are discharged.
 17. Theautomated external defibrillator of claim 1 wherein the controlcomprises at least one of a button and the indicator.
 18. (canceled) 19.The automated external defibrillator of claim 1 wherein the indicatorcomprises at least one of a visual indicator, a lighted display, anaudio indicator, a verbal indicator and a haptic indicator.
 20. Theautomated external defibrillator of claim 1 comprising a motion sensorconfigured to generate motion signals arising from chest compressionsapplied to the patient, and wherein the one or more computer processorsare configured to receive the generated motion signals arising fromchest compressions applied to the patient and determine at least one ofdepth and rate of chest compressions based on the received motionsignals.
 21. The automated external defibrillator of claim 20 wherein,when the automated external defibrillator is in the adult operatingmode, the one or more computer processors are configured to compare theat least one of depth and rate of chest compressions to a desired rangeand provide chest compression feedback to a user.
 22. The automatedexternal defibrillator of claim 21 wherein the chest compressionfeedback comprises at least one of visual feedback, audio feedback andhaptic feedback.
 23. The automated external defibrillator of claim 20comprising a user interface configured to provide a visual display ofnumerical values of the determined at least one of depth and rate ofchest compressions when the automated external defibrillator is set to abasic life support mode.
 24. The automated external defibrillator ofclaim 23 wherein, when the automated external defibrillator is in theadult operating mode, the one or more computer processors are configuredto compare the at least one of depth and rate of chest compressions to adesired range and provide chest compression feedback to a user.
 25. Theautomated external defibrillator of claim 23 wherein, when the automatedexternal defibrillator is in the pediatric operating mode, the userinterface is configured to refrain from providing chest compressionfeedback to a user.
 26. The automated external defibrillator of claim 1wherein the one or more computer processors are configured to cause theone or more capacitors to be charged to a voltage that is greater whenthe operating mode is in the adult operating mode than when theoperating mode is in the pediatric operating mode.
 27. The automatedexternal defibrillator of claim 1 wherein the one or more computerprocessors are configured to cause a resistance in a circuit between theone or more capacitors and the patient to be greater when the operatingmode is in the pediatric operating mode than when the operating mode isin the adult operating mode.
 28. The automated external defibrillator ofclaim 1 wherein the one or more processors are configured to analyze oneor more portions of the ECG signal, wherein the analysis differs betweenthe pediatric operating mode and the adult operating mode. 29.-41.(canceled)